When you are completely naked and in awe of the truth, your soul develops a greater appreciation for the genuine.
I have been through changes and experiences, not always psychedelic, which have left a profound impact on the way I react to stimuli. Deep, genuine and powerful actions are something that I have a lot, it's more like the actions that lack authenticity have been and still are being cut out of my soul, being replaced with something that springs out of calm and tranquility, with a more timeless flow of existence.
Meditation has been the best way for me of understanding these changes. When you exist in the present moment, it unfolds and reveals itself, it pulls down the curtain of appearances and explodes with depth. The eye of consciousness shines its light removing all that is unclear, and eroding the wall of creation leaving shapes that are infinitely beautiful and intricate in their impossible existence, and that is the real nature of things, or Dharma.
The facial characteristics or expressions are caused by nervous impulses telling certain muscles to contract, and how hard they should do so. If I understand you correctly, we can conclude that the impulses travel to more muscles, and are more intense, which means that the place from which they spring is more radiating and warm
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Interesting topic to think about, thank you for posting this